Methods and apparatus for passive cooling of electronic units

Abstract

A cooling apparatus for an electronic unit is described which includes a first plate, a second plate, and a controlling mechanism. The first and second plates are generally planar and have holes formed therethrough. The controlling mechanism is operable to move the first plate with respect to the second plate. A first position for movement is where more of the holes in the first plate and the second plate are substantially aligned than are not aligned. A second position is where more of the holes in the first plate and the second plate are not aligned than are aligned.

1 . A cooling apparatus for an electronic unit comprising: 
 a generally planar first plate having holes formed therethrough;    a generally planar second plate having holes formed therethrough; and    a controlling mechanism operable to move said first plate with respect to said second plate, said mechanism operable to cause said first plate to move to a first position being where more holes in said first plate and said second plate are substantially aligned than not aligned, said mechanism operable to cause said first plate to move to a second position being where more holes in said first plate and said second plate are not aligned than are substantially aligned.    
   
   
       2 . A cooling apparatus according to  claim 1  wherein said second plate forms a top portion of a chassis for the electronic unit.  
   
   
       3 . A cooling apparatus according to  claim 1  wherein said first plate and said second plate are generally parallel to one another.  
   
   
       4 . A cooling apparatus according to  claim 1  wherein said first plate is free to move with respect to said second plate in one direction and constrained with respect to said second plate in other orthogonal directions.  
   
   
       5 . A cooling apparatus according to  claim 4  wherein said first plate comprises side walls and protrusions extending inward from said side walls, said protrusions engaging the electronic unit.  
   
   
       6 . A cooling apparatus according to  claim 1  wherein the holes in said first plate and said second plate are surrounded by conical protrusions.  
   
   
       7 . A cooling apparatus according to  claim 1  wherein said controlling mechanism controls a position of said first plate based on an input from a sensor.  
   
   
       8 . A cooling apparatus according to  claim 1  wherein said controlling mechanism comprises one or more of a solenoid, mechanical levers, a spring-loaded device, and a temperature controlled device.  
   
   
       9 . A cooling apparatus according to  claim 1  wherein said first plate and said second plate are configured with a substantially similar pattern of holes formed therethrough.  
   
   
       10 . A chassis for an electronic unit comprising: 
 a top having holes formed therethrough; and    a generally planar plate movably mounted with respect to said top in said chassis, said plate substantially parallel to said top and having holes formed therethrough.    
   
   
       11 . A chassis according to  claim 10  wherein said plate is movable to a first position where more of the holes in said top and said plate are aligned than are not aligned, and movable to a second position where more of the holes in said top and said plate are not aligned than are aligned.  
   
   
       12 . A chassis according to  claim 10  wherein the holes in said top and said plate are surrounded by conical protrusions.  
   
   
       13 . A chassis according to  claim 10  further comprising a controlling mechanism operable to move said planar plate with respect to said top.  
   
   
       14 . A chassis according to  claim 10  wherein said controlling mechanism comprises one of a manual control, a solenoid, a switch, a spring-loaded device, and a temperature controlled device.  
   
   
       15 . A chassis according to  claim 9  wherein said planar plate is free to move with respect to said top in one direction and constrained with respect to said top in other orthogonal directions.  
   
   
       16 . A chassis according to  claim 15  wherein said planar plate comprises side walls and protrusions extending inward from said side walls, said protrusions engaging said chassis.  
   
   
       17 . A chassis according to  claim 15  wherein said planar plate and said top are configured with a substantially similar pattern of holes therethrough.  
   
   
       18 . A method for constructing a chassis for an electronic unit that is compatible for active cooling, passive cooling and protected from ingress of fluids, said method comprising: 
 forming holes in a top of the chassis;    forming holes in a plate; and    movably mounting the plate above, and substantially parallel to the top of the chassis, the mounting including at least one position where more of the holes in the plate and the top substantially align with one another than do not align and at least one position where more of the holes do not substantially align with one another than do substantially align.    
   
   
       19 . A method according to  claim 18  further comprising: 
 forming a protrusion around each individual hole in the top of the chassis; and    forming a protrusion around each individual hole in the plate to be mounted above the chassis.    
   
   
       20 . A method according to  claim 18  further comprising configuring the electronic unit with a controlling mechanism, the controlling mechanism operable to move the plate with respect to the top of the chassis for substantial alignment and non-alignment of the holes formed in the top of the chassis and the plate mounted above.  
   
   
       21 . A method according to  claim 20  movably mounting the plate comprises: 
 forming channels in sides of the chassis;    configuring the plate with side walls and inward facing protrusions; and    engaging the inward facing protrusions with the channels.